refactor: delete dead legacy payment code from ApiService

Verified zero remaining callers for each before deleting (grepped
src/app for every method name individually), not assumed from the
earlier commit's dead-code note.

Deleted from api.service.ts:
- createPayment() - legacy direct QR creation (POST {qrBaseUrl}/qr)
- createCartPayment() - legacy /cart payment creation, client-sent amount
- createPaymentIntent() - superseded by @marketplaces/payment's gateway
- checkCartPaymentStatus(), checkCartCardPaymentStatus(), checkPaymentStatus()
  - legacy QR/card status polls, superseded by the same gateway
- resolvePaymentQrId/resolvePaymentQrUrl/resolvePaymentLink/
  resolveBankPaymentUrl - QrCreateResponse field-normalization helpers,
  no longer had a caller once the methods above were gone
- Types: QrCreateRequest, QrCreateResponse, CartPaymentRequest,
  PaymentIntentRequest, QrDynamicStatusResponse
- Fields: qrBaseUrl, cartPaymentPartnerId - no longer read by anything
- Imports: HttpHeaders, environment - no longer used in this file

Did NOT touch createOrder() or createCheckoutSession() - both still have
live callers in cart.component.ts, confirmed before deciding what to keep.

cart.component.ts: corrected the createPaymentIntent() comment, which
referenced the deleted method/helper names, to name what actually got
deleted instead of what was merely "dead as of that commit."

docs/backend/FRONTEND-API-SURFACE-COMPLETE.md: moved the 4 now-deleted
QR/card endpoints out of the "still live" legacy table into a dated removal
note - the doc's own premise is "every endpoint this codebase currently
calls," so it was wrong to leave them listed as called once they weren't.
Legacy-undocumented count corrected 15->11, total 97->93.

Verified: production build succeeds (no dangling references), 247/247 unit
tests, arch:check clean.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/backend/FRONTEND-API-SURFACE-COMPLETE.md

@@ -68,13 +68,11 @@ These come from `BACKEND-API-REFERENCE.md`, not `docs/backend/`. Base URL is `en
 | POST | `/items/{itemID}/questiion` | `api.service.ts` | ❌ Undocumented — product Q&A (note: `questiion` typo is load-bearing, do not silently "fix" without checking the live backend uses the same typo) |
 | POST | `/items/{itemID}/notify-me` | `api.service.ts` | ❌ Undocumented — back-in-stock subscription |
 | POST | `/purchase-email` | `api.service.ts` | ❌ Undocumented — post-purchase email collection |
-| POST | `{qrBaseUrl}/qr` | `api.service.ts` | ❌ Undocumented — direct QR payment creation |
-| POST | `/cart` | `api.service.ts` | ❌ Undocumented — legacy payment creation, client-sent `amount` (superseded by §2 below for new checkout flow; **still live** for any caller not yet migrated) |
-| GET | `{qrBaseUrl}/qr/dynamic/{partnerId}/{qrId}` | `api.service.ts` | ❌ Undocumented — QR payment status poll |
-| GET | `{qrBaseUrl}/card/{partnerId}/{orderId}` | `api.service.ts` | ❌ Undocumented — card payment status poll |
 | POST | `/orders` | `api.service.ts` | ❌ Undocumented — records a paid cart as a backoffice order, fire-and-forget |
 
-**Recommendation:** these 15 need their own contract doc if they are staying, or a deprecation timeline if `/api/v2/storefront/*` replaces them. Right now they are simply undocumented and live — the single biggest gap in `docs/backend/`.
+**Recommendation:** these 11 need their own contract doc if they are staying, or a deprecation timeline if `/api/v2/storefront/*` replaces them. Right now they are simply undocumented and live — the single biggest gap in `docs/backend/`.
+
+**Removed 2026-08-21, no longer called by this codebase:** `POST {qrBaseUrl}/qr` (direct QR creation), `POST /cart` (legacy payment creation with client-sent `amount`), `GET {qrBaseUrl}/qr/dynamic/{partnerId}/{qrId}` and `GET {qrBaseUrl}/card/{partnerId}/{orderId}` (status polls). §2's checkout flow made these dead in code (`createPaymentIntent`) as of the earlier `@marketplaces/payment` integration commit; confirmed zero remaining callers and deleted the dead `ApiService` methods, request/response types, and unused fields (`qrBaseUrl`, `cartPaymentPartnerId`) in the same pass. If a real backend still serves these endpoints, they are now backend-only surface with no frontend caller — decide their fate independently of this doc.
 
 ---
 
@@ -373,8 +371,8 @@ The frontend added a client-side guard against double-submitting checkout (a rea
 |---|---|
 | ✅ Specified | 54 |
 | ⚠️ Inferred (needs confirmation) | 24 |
-| ❌ Undocumented (legacy) | 15 |
-| **Total distinct endpoints called** | **97** |
+| ❌ Undocumented (legacy) | 11 |
+| **Total distinct endpoints called** | **93** |
 
 (§0's 3 Telegram endpoints count as Specified+live; its 4 ed25519 endpoints count as Specified+not-built — both are real, named endpoints with a known shape, distinct from §1's "no contract exists anywhere" undocumented status.)
 

src/app/pages/cart/cart.component.ts

@@ -333,12 +333,12 @@ export class CartComponent implements OnDestroy {
   /**
    * Superseded api.service.ts's createPaymentIntent (POST
    * /api/v2/storefront/payments/intents, our own inferred contract) with
-   * @marketplaces/payment's real, published one. That method and the
+   * @marketplaces/payment's real, published one. That method, createPayment
+   * (legacy /qr), createCartPayment (legacy /cart), checkCartPaymentStatus,
+   * checkCartCardPaymentStatus, checkPaymentStatus, and the
    * QrCreateResponse-based resolvePaymentQrId/resolvePaymentQrUrl/
-   * resolvePaymentLink/resolveBankPaymentUrl helpers on ApiService are dead
-   * code as of this change - left in place rather than deleted in the same
-   * pass that adds a new external dependency, so a revert doesn't also need
-   * to resurrect deleted code.
+   * resolvePaymentLink/resolveBankPaymentUrl helpers - all now deleted from
+   * ApiService, confirmed dead first (zero remaining callers) before removal.
    */
   private createPaymentIntent(
     session: import('../../services/api.service').CheckoutSessionResponse,

src/app/services/api.service.ts

@@ -1,58 +1,11 @@
 import { Injectable } from '@angular/core';
-import { HttpClient, HttpHeaders, HttpParams } from '@angular/common/http';
+import { HttpClient, HttpParams } from '@angular/common/http';
 import { Observable, timer } from 'rxjs';
 import { map, retry } from 'rxjs/operators';
 import { CategoryApiModel, DeliveryOption, Item, Subcategory } from '../models';
 import { normalizeDeliveryOption, normalizeOptionalNumber } from '../utils/normalization.utils';
-import { environment } from '../../environments/environment';
 import { ApiConfigService } from '../core/config/api-config.service';
 
-export interface QrCreateRequest {
-  qrtype: 'QRDynamic';
-  amount: number;
-  currency: 'RUB';
-  partnerqrID?: string;
-  qrDescription?: string;
-  Userid?: string;
-  Reference?: string;
-  RedirectUrl?: string;
-}
-
-export interface QrCreateResponse {
-  qrId?: string;
-  qrID?: string;
-  nspkID?: string;
-  nspkId?: string;
-  nspkurl?: string;
-  orderID?: string;
-  url?: string;
-  bankUrl?: string;
-  status?: string;
-  qrStatus?: string;
-  qrExpirationDate?: string;
-  qrTTL?: number;
-  payload?: string;
-  Payload?: string;
-  qrUrl?: string;
-  partnerqrID?: string | number;
-  partnerID?: string | number;
-  partnerId?: string | number;
-  PartnerID?: string | number;
-}
-
-export interface CartPaymentRequest {
-  amount: number;
-  currency: string;
-  siteuserID: string;
-  siteorderID: string;
-  redirectUrl: string;
-  telegramUsername: string;
-  paymentMethod: 'qr' | 'card';
-  qrDescription?: string;
-  customerID?: string;
-  items: Array<{ itemID: number; price: number; name: string; quantity?: number; delivery?: DeliveryOption[] }>;
-}
-
 /**
  * Server-authoritative checkout. Contract: PHASE-1-MONEY-FX-PAYMENTS-CONTRACT.md §5.2.
  * No `amount` or `price` field anywhere in this pair - the backend prices
@@ -88,18 +41,6 @@ export interface CheckoutSessionResponse {
   expiresAt: string;
 }
 
-/**
- * References checkoutSessionId only - the amount charged is read
- * server-side from the session, never re-sent by the client (contract §5.2).
- * merchantReference is PARTNER-PROVISIONING-API-CONTRACT.md's RoutingContext
- * field: our own correlation id, echoed back on every related event.
- */
-export interface PaymentIntentRequest {
-  checkoutSessionId: string;
-  paymentMethod: 'qr' | 'card';
-  merchantReference: string;
-}
-
 export interface CreateOrderRequest {
   /**
    * No `price` field: the backend must price each line item from its own
@@ -120,28 +61,10 @@ export interface CreateOrderResponse {
   currency: string;
 }
 
-export interface QrDynamicStatusResponse {
-  additionalInfo: string;
-  paymentPurpose: string;
-  amount: number;
-  code: string;
-  createDate: string;
-  currency: string;
-  order: string;
-  status: string;
-  qrId: string;
-  transactionDate: string;
-  transactionId: number;
-  qrExpirationDate: string;
-}
-
 @Injectable({
   providedIn: 'root'
 })
 export class ApiService {
-  private readonly qrBaseUrl = (environment as any).qrApiUrl as string;
-  private readonly cartPaymentPartnerId = 'web-97ec-9c57-4dde-9037-3a68f7f83750';
-
   private readonly retryConfig = {
     count: 2,
     delay: (_error: unknown, retryCount: number) => timer(Math.pow(2, retryCount) * 500)
@@ -669,21 +592,6 @@ export class ApiService {
     return this.http.post<{ message: string }>(`${this.baseUrl}/items/${itemID}/questiion`, body);
   }
 
-  createPayment(payload: QrCreateRequest, headers?: { authorizationKey?: string; userIdValue?: string }): Observable<QrCreateResponse> {
-    let httpHeaders = new HttpHeaders();
-    if (headers?.authorizationKey) {
-      httpHeaders = httpHeaders.set('authorization-key', headers.authorizationKey);
-    }
-    if (headers?.userIdValue) {
-      httpHeaders = httpHeaders.set('userid-value', headers.userIdValue);
-    }
-    return this.http.post<QrCreateResponse>(`${this.qrBaseUrl}/qr`, payload, { headers: httpHeaders });
-  }
-
-  createCartPayment(payload: CartPaymentRequest): Observable<QrCreateResponse> {
-    return this.http.post<QrCreateResponse>(`${this.baseUrl}/cart`, payload);
-  }
-
   /**
    * Creates a server-priced checkout session. Contract §5.2 - the frontend
    * sends offer ids and quantities only; the response carries the total that
@@ -694,16 +602,6 @@ export class ApiService {
     return this.http.post<CheckoutSessionResponse>('/api/v2/storefront/checkout', payload);
   }
 
-  /**
-   * Creates a payment intent against an existing checkout session. Same
-   * response shape as createCartPayment (QrCreateResponse) - this replaces
-   * how the amount is determined, not the QR/card provider integration
-   * itself, which Phase 1 does not redesign.
-   */
-  createPaymentIntent(payload: PaymentIntentRequest): Observable<QrCreateResponse> {
-    return this.http.post<QrCreateResponse>('/api/v2/storefront/payments/intents', payload);
-  }
-
   /**
    * Records the just-paid cart as a backoffice order (POST /orders). Fire-and-forget
    * from the caller's perspective - a failure here must never block the existing
@@ -713,45 +611,6 @@ export class ApiService {
     return this.http.post<CreateOrderResponse>(`${this.baseUrl}/orders`, payload);
   }
 
-  checkCartPaymentStatus(qrId: string): Observable<QrDynamicStatusResponse> {
-    return this.http.get<QrDynamicStatusResponse>(
-      `${this.qrBaseUrl}/qr/dynamic/${this.cartPaymentPartnerId}/${encodeURIComponent(qrId)}`
-    );
-  }
-
-  checkCartCardPaymentStatus(orderId: string): Observable<QrDynamicStatusResponse> {
-    return this.http.get<QrDynamicStatusResponse>(
-      `${this.qrBaseUrl}/card/${this.cartPaymentPartnerId}/${encodeURIComponent(orderId)}`
-    );
-  }
-
-  checkPaymentStatus(partnerQrId: string, qrId: string): Observable<QrDynamicStatusResponse> {
-    return this.http.get<QrDynamicStatusResponse>(
-      `${this.qrBaseUrl}/qr/dynamic/${encodeURIComponent(partnerQrId)}/${encodeURIComponent(qrId)}`
-    );
-  }
-
-  resolvePaymentQrId(response: QrCreateResponse): string {
-    return response.qrId ?? response.qrID ?? response.nspkID ?? response.nspkId ?? response.orderID ?? '';
-  }
-
-  resolvePaymentLink(response: QrCreateResponse): string {
-    return response.nspkurl ?? response.Payload ?? response.payload ?? response.qrUrl ?? '';
-  }
-
-  resolveBankPaymentUrl(response: QrCreateResponse): string {
-    return response.bankUrl ?? response.url ?? '';
-  }
-
-  resolvePaymentQrUrl(response: QrCreateResponse): string {
-    const paymentLink = this.resolvePaymentLink(response);
-    if (paymentLink) {
-      return `https://api.qrserver.com/v1/create-qr-code/?size=256x256&margin=8&data=${encodeURIComponent(paymentLink)}`;
-    }
-
-    return response.qrUrl ?? '';
-  }
-
   submitPurchaseEmail(emailData: {
     email: string;
     phone?: string;